Effects of sinapic acid on oxidative DNA damage in V79 cell line

Phenolic compounds, due to their antioxidant properties, play an important role in the prevention of various degenerative disorders or diseases related to oxidative damage. Sinapic acid (SA), a phenolic compound, is widely distributed in the plant kingdom and commonly consumed in human diets. SA has been described as a chain-breaking antioxidant that probably acts as a radical scavenger. SA was reported to exhibit a protection against H2O2-mediated cytotoxicity in a dose-dependent manner. SA is believed to be therapeutically beneficial and non-toxic. However the data about the genotoxicity of SA are limited. In this study, the genotoxic/antigenotoxic activities of SA were evaluated in V79 cells by alkaline single cell gel electrophoresis. No significant increase in DNA strand breakage expressed as DNA tail intensity was observed below 1000 µM; however, at the concentrations of 1000-5000 µM SA alone caused an increase in DNA damage in a dose-dependent manner. At the concentrations of 50-2000 µM, SA seemed to significantly decrease H2O2-induced DNA damage. However, at the highest concentration of 5000 µM, SA did not decrease H2O2-induced DNA damage in V79 cells. In conclusion, at low concentrations SA might protect against various oxidative stress related-diseases by reducing oxidative DNA damage

Resveratrolün Farklı Hücre Hatlarında MTT ve NKA Yöntemleri ile Değerlendirilen Sitotoksik Etkileri

Oksidatif stres, reaktif oksijen bileşiklerinin üretimi ile antioksidan savunma sistemlerinin dengesinin bozulmasını tanımlayan bir terimdir. Oksidatif stres, inflamasyon kanser, nörodejeneratif bozukluklar ve kardiyovasküler hastalıklar gibi birçok hastalığın gelişmesinde rol oynamaktadır. Bitkisel fenolik bileşiklerin antioksidan etkili oldukları ve bu nedenle anti kanser etkileri oldukları öne sürülmektedir. Resveratrol (RV), üzüm, fındık, yaban mersini ve ahududu gibi pekçok bitkisel üründe bulunan, doğal olarak oluşan polifenolik bir bileşiktir. RV'nin antioksidan, antiinflamatuvar ve antikanser etkileri olduğu gösteren çalışmalar bulunmaktadır. Ancak RV'nin özellikle kanserin önlenmesinde koruyucu etkilerinin olmadığını da iddia edilmektedir. Bu çalışmada, insan meme adenokarsinoma (MDA-MB 231), insan servikal kanser (HeLa) ve Çin hamster akciğer fibroblast (V79) hücrelerinde RV'nin sitotoksik etkileri, 24 saat inkübasyon sonrasında Nötral Kırmızı Alım (NKA) ve 3-(4,5-dimetiltiyazol-2-il)-2,5- difeniltetrazolyum bromür (MTT) yöntemleri ile değerlendirilmiştir. Her iki sitotoksisite yönteminde de benzer sonuçlar elde edilmiştir. 2-400 µM aralığında, RV'ün tüm hücre tiplerinde belirgin bir sitotoksik etkisi olmadığı görülmüştür. Hatta en yüksek konsatrasyonlarda bile neredeyse hiç sitotoksik etkileri olmamıştır. Bu nedenle IC50 değerleri, bu konsantrasyonaralığında hesaplanamamıştır.Oxidative stress is the state of imbalance between the level of antioxidant defence system and production of reactive oxygen species (ROS) and is involded in the progression of several diseases such as inflammation, cancer, neurodegenerative disorders and cardiovascular diseases. It is suggested that plant polyphenols may act as antioxidants and therefore it has anti-cancer activities. Resveratrol (RV), is a naturally occuring polyphenolic compound which is found in many plant species including grapes, nuts, blueberries and raspberries. Data indicated that it has anti-oxidant, anti-inflamatory and anti-cancer activities. But there are also some studies reported that RV has not protective effects aganist cancer. In this study, the cytotoxicity of RV in human breast adenocarcinoma (MDA-MB 231), human cervical cancer (HeLa) and Chinese hamster lung fibroblast (V79) cells were evaluated by Neutral Red uptake assay (NRU) and MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assays after incubation at 24 h. We obtained more or the less same results by two cytotoxicity assays. In the concentrations between 2-400 mM, RV seemed not to induce a pronounced cytotoxicity in all cell types. Even at highest concentrations, it showed almost no cytotoxic effects. So the IC50 values were not calculated at the studied concentrations

Anticarcinogenic Effects of the Ethanolic Extract of Salix aegyptiaca in Colon Cancer Cells: Involvement of Akt/PKB and MAPK Pathways

The bark from Salix species of plants has been traditionally consumed for its antiinflammatory properties. Because inflammation frequently accompanies the progress of colorectal cancer (CRC), we have evaluated the anticancer properties of the ethanolic extract from the bark (EEB) of S. aegyptiaca, a Salix species endogenous to the Middle East, using HCT-116 and HT29 CRC cell lines. Fresh bark from S. aegyptiaca was extracted with ethanol, fractionated by solvent-solvent partitioning and the fractions were analyzed by tandem mass spectrometry. Catechin, catechol, and salicin were the most abundant constituents of the extract. Interestingly, EEB showed the highest anticancer effect in the colon cancer cells followed by its fractions in ethyl acetate and water, with catechin, catechol, and salicin showing the least efficacy. EEB could strongly reduce the proliferation of the cancer cells, but not of CCD-18Co, normal colon fibroblast cell line. Accompanying this was cell cycle arrest at G1/S independent of DNA damage in the cancer cells, induction of apoptosis through a p53 dependent pathway and an inhibition of PI3K/Akt and MAP Kinase pathways at levels comparable to known commercial inhibitors. We propose that the combination of the polyphenols and flavonoids in EEB contributes toward its potent anticarcinogenic effects. [Supplementary materials are available for this article. Go to the publisher's online edition of Nutrition and Cancer for the following free supplemental resource(s): Supplementary Figure 1 and Supplementary Figure 2.

Protective effects of rosmarinic acid on sepsis-induced DNA damage in the liver of Wistar albino rats

Sepsis is an imbalance between pro and anti-inflammatory responses. Sepsis induced multiple organ failure that is associated with mortality is characterized by liver, renal, cardiovascular and pulmonary dysfunction and reactive oxygen species (ROS) are believed to be involved in the development of sepsis. Plant polyphenols may act as antioxidants by different mechanisms such as free radical scavenging, metal chelation and protein binding. Data indicates possible beneficial effects of plant derived phenolic compounds against sepsis. Rosmarinic acid (RA) (α-O-caffeoyl-3,4-dihydroxyphenyllactic acid) is a phenolic compound commonly found in various plants such as Rosmarinus officinalis (rosemary), Origanum vulgare (oregano), Thymus vulgaris (thyme), Mentha spicata (spearmint), Perilla frutescens (perilla), Ocimum basilicum (sweet basil) and several other medicinal plants. It has been shown that RA has many biological activities including antioxidant, anti-inflammatory, antiallergic, anticancer and actimicrobial and is widely used in cosmetic and food industry. In the present study, we aimed to determine the protective effects of RA against the oxidative DNA damage induced by sepsis in Wistar albino rats. The rats were divided into four groups; sham, sepsis induced, RA-treated, RA treated and sepsis induced groups. Wistar rats were subjected to sepsis by cecal ligation puncture. The liver tissues were carefully dissected from their attachments and totally excised. The concentrations of the hepatic tissue cells were adjusted to approximately 2 x 106 cells/ml. Standard and formamidopyrimidine-DNA glycosylase (Fpg) modified comet assay described by Singh et al were used. There were no statistically significant differences in terms of tail length, tail intensity and tail moment between the sham group and the RA-treated groups (p>0.05). The DNA damage was found significantly higher in the sepsis-induced group compared to the sham group (p0.05), and the DNA damage was found significantly higher in the sepsis-induced group compared to the sham group (p<0.05). RA treatment in the sepsis-induced group was found to decrease the DNA damage significantly (p<0.05). In conclusion, RA might have a role in the prevention of sepsis-induced oxidative damage not only by decreasing the DNA damage but also by increasing DNA repair capacity of the animals

Ursolik asit sıçanlardaki diyabete karşı yararlı olabilir mi?

Objective: Diabetes mellitus, a heteregenous metabolic and chronic disease, is a growing health problem especially in developing countries. It is claimed that diabetes associated with increased formation of free radicals and decrease in antioxidant potential and also alterations in lipid profile and enzyme levels. Ursolic acid is commonly used in traditional Chinese medicine due to its beneficial effects. The aim of this study was to investigate the effects of ursolic acid on streptozotocin-induced diabetes in Wistar albino rats. Methods: DNA damage was evaluated in the blood and liver cells of rats by alkaline comet assay. The activities of antioxidant enzymes, oxidative stress parameters, biochemical parameters, hepatic enzyme levels and lipid profile parameters were also evaluated. Results: The results of this study demonstrate that diabetes caused genotoxic damage, changes in hepatic enzyme and lipid profile, biochemical and antioxidant enzyme activities and oxidative stress parameters in rats. Ursolic acid was found to be protective against diabetes induced effects in blood and liver samples of rats. Conclusions: According to our results, it seems that ursolic acid may be beneficial against diabetes and its adverse effects in rats.Amaç: Karmaşık bir metabolik ve kronik hastalık olan diyabet özellikle gelişmekte olan ülkelerde büyüyen bir sağlık sorunudur. Diyabetin serbest radikal oluşumu ve antioksidan potansiyelde azalma ile birlikte lipit profili ve enzim düzeylerinde değişikliklerle ilişkili olduğu iddia edilmektedir. Ursolik asit yararlı etkileri nedeniyle geleneksel Çin tıbbında yaygın olarak kullanılmaktadır. Bu çalışmanın amacı, ursolik asidin Wistar albino sıçanlarda streptozotosin ile oluşturulan diyabete etkilerini değerlendirmektir. Metod: DNA hasarı sıçanların kan ve karaciğer hücrelerinde alkali comet yöntemiyle değerlendirilmiştir. Antioksidan enzimlerin aktiviteleri, oksidatif stres göstergeleri, biyokimyasal parametreler, hepatik enzim düzeyleri, lipit profil göstergeleri de değerlendirilmiştir. Bulgular: Bu çalışmanın sonuçları sıçanlarda diyabetin genotoksik hasara, hepatik enzimlerde ve lipit profilinde, biyokimyasal ve antioksidan enzim aktivitelerinde ve oksidatif stres parametrelerinde değişikliğe neden olduğunu göstermiştir. Ursolik asidin sıçanların kan ve karaciğer örneklerinde diyabetin neden olduğu etkilere karşı koruyucu olduğu bulunmuştur. Sonuç: Sonuçlarımıza göre, ursolik asidin sıçanlardaki diyabet ve diyabetin istenmeyen etkilerine karşı yararlı olabileceği görülmektedir

Use of side chain thiophene containing copolymer as a non-ionic gel-dielectric material for sandwich OFET assembly

The performances of non-ionic-gel-gated poly(3-hexylthiophene) [P3HT] transistors were investigated by using poly(methyl methacrylate) [PMMA] homopolymer and poly(3-methylthienyl methacrylate-co-methyl methacrylate) [P(MMA-co-MTM)] copolymer alternatively in the gel of a novel organic field effect transistors (OFETs) assembly. The results are quite remarkable and open a new approach to obtain high mobility and low operating voltage. This new fabrication process, namely the sandwich model with a non-ionic-gel-dielectric material has been improved by using a compatible copolymer [P(MMA-co-MTM)] in terms of chemical similarity at the interface of the active and dielectric layers. The gel material proposed, included side chain thiophene-based copolymer, has been found to enhance the mobility of the device for almost two times and decreases the working and threshold voltages slightly as well. (C) 2012 Elsevier B.V. All rights reserved